Design of Digital Voltmeter with High Precision and Automatic Range Conversion

This paper presents the design proposal of high precision digital voltmeter,by taken single chip microcontroller AT89S52 as the core,A/D converter chip LTC1865 as the foundation,and combined with the circuit of automatic range conversion.The voltmeter can measure the voltage range from 0V to 400V precisely and automatically.The test results show that the voltmeter has the features such as:high precision of measuremont,stable performance,fast conversion and high definition of display,and has the very good practical application value.